Commit c8a7ba9e authored by Thomas Chou's avatar Thomas Chou

dm: implement a Timer uclass

Implement a Timer uclass to work with lib/time.c.
Signed-off-by: default avatarThomas Chou <thomas@wytron.com.tw>
Acked-by: default avatarSimon Glass <sjg@chromium.org>
parent bcae80e9
......@@ -58,6 +58,8 @@ source "drivers/spi/Kconfig"
source "drivers/thermal/Kconfig"
source "drivers/timer/Kconfig"
source "drivers/tpm/Kconfig"
source "drivers/usb/Kconfig"
......
......@@ -48,6 +48,7 @@ obj-y += pcmcia/
obj-y += dfu/
obj-y += rtc/
obj-y += sound/
obj-y += timer/
obj-y += tpm/
obj-y += twserial/
obj-y += video/
......
menu "Timer Support"
config TIMER
bool "Enable Driver Model for Timer drivers"
depends on DM
help
Enable driver model for Timer access. It uses the same API as
lib/time.c. But now implemented by the uclass. The first timer
will be used. The timer is usually a 32 bits free-running up
counter. There may be no real tick, and no timer interrupt.
endmenu
#
# Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
#
# SPDX-License-Identifier: GPL-2.0+
#
obj-$(CONFIG_TIMER) += timer-uclass.o
/*
* Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <timer.h>
/*
* Implement a Timer uclass to work with lib/time.c. The timer is usually
* a 32 bits free-running up counter. The get_rate() method is used to get
* the input clock frequency of the timer. The get_count() method is used
* get the current 32 bits count value. If the hardware is counting down,
* the value should be inversed inside the method. There may be no real
* tick, and no timer interrupt.
*/
int timer_get_count(struct udevice *dev, unsigned long *count)
{
const struct timer_ops *ops = device_get_ops(dev);
if (!ops->get_count)
return -ENOSYS;
return ops->get_count(dev, count);
}
unsigned long timer_get_rate(struct udevice *dev)
{
struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
return uc_priv->clock_rate;
}
UCLASS_DRIVER(timer) = {
.id = UCLASS_TIMER,
.name = "timer",
.per_device_auto_alloc_size = sizeof(struct timer_dev_priv),
};
......@@ -69,6 +69,9 @@ typedef struct global_data {
struct udevice *dm_root_f; /* Pre-relocation root instance */
struct list_head uclass_root; /* Head of core tree */
#endif
#ifdef CONFIG_TIMER
struct udevice *timer; /* Timer instance for Driver Model */
#endif
const void *fdt_blob; /* Our device tree, NULL if none */
void *new_fdt; /* Relocated FDT */
......
......@@ -57,6 +57,7 @@ enum uclass_id {
UCLASS_SPI_GENERIC, /* Generic SPI flash target */
UCLASS_SYSCON, /* System configuration device */
UCLASS_THERMAL, /* Thermal sensor */
UCLASS_TIMER, /* Timer device */
UCLASS_TPM, /* Trusted Platform Module TIS interface */
UCLASS_USB, /* USB bus */
UCLASS_USB_DEV_GENERIC, /* USB generic device */
......
/*
* Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef _TIMER_H_
#define _TIMER_H_
/*
* Get the current timer count
*
* @dev: The Timer device
* @count: pointer that returns the current timer count
* @return: 0 if OK, -ve on error
*/
int timer_get_count(struct udevice *dev, unsigned long *count);
/*
* Get the timer input clock frequency
*
* @dev: The Timer device
* @return: the timer input clock frequency
*/
unsigned long timer_get_rate(struct udevice *dev);
/*
* struct timer_ops - Driver model Timer operations
*
* The uclass interface is implemented by all Timer devices which use
* driver model.
*/
struct timer_ops {
/*
* Get the current timer count
*
* @dev: The Timer device
* @count: pointer that returns the current timer count
* @return: 0 if OK, -ve on error
*/
int (*get_count)(struct udevice *dev, unsigned long *count);
};
/*
* struct timer_dev_priv - information about a device used by the uclass
*
* @clock_rate: the timer input clock frequency
*/
struct timer_dev_priv {
unsigned long clock_rate;
};
#endif /* _TIMER_H_ */
......@@ -6,6 +6,9 @@
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <timer.h>
#include <watchdog.h>
#include <div64.h>
#include <asm/io.h>
......@@ -37,6 +40,52 @@ unsigned long notrace timer_read_counter(void)
extern unsigned long __weak timer_read_counter(void);
#endif
#ifdef CONFIG_TIMER
static int notrace dm_timer_init(void)
{
struct udevice *dev;
int ret;
if (!gd->timer) {
ret = uclass_first_device(UCLASS_TIMER, &dev);
if (ret)
return ret;
if (!dev)
return -ENODEV;
gd->timer = dev;
}
return 0;
}
ulong notrace get_tbclk(void)
{
int ret;
ret = dm_timer_init();
if (ret)
return ret;
return timer_get_rate(gd->timer);
}
unsigned long notrace timer_read_counter(void)
{
unsigned long count;
int ret;
ret = dm_timer_init();
if (ret)
return ret;
ret = timer_get_count(gd->timer, &count);
if (ret)
return ret;
return count;
}
#endif /* CONFIG_TIMER */
uint64_t __weak notrace get_ticks(void)
{
unsigned long now = timer_read_counter();
......
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